20180208PAC to Staff Standpipe RAS - Assessment.docx

PacifiCorp Main Grid Planning
PRC-(012 through 014)-WECC-CRT2
Attachment B RAS Assessment
RAS Name
Standpipe LAPS
Reporting Party
PacifiCorp
Group Conducting Assessment
PacifiCorp Main Grid Planning
Assessment Date
6/9/15
Review the scheme purpose and impact to ensure proper classification, is it (still) necessary, does it serve the intended purposes, and does it continue to meet current performance requirements.
The Standpipe LAPS is designed to prevent low voltage conditions on 230 kV system near Badwater and Spence substations following the N-1 loss of the Platte to Standpipe230 kV line in conjunction with heavy output from wind generation facilities in south-central Wyoming. The scheme trips wind generation at Foote Creek and High Plains.
The StandpipeLAPS is listed as a Local Area Protection Scheme. This designation is appropriate due to the level of generation tripping (<1000 MW) andload loss exposure (<300 MW). Impacts are limited to low voltage conditions on 230 kV system near Badwater and Spence substations for failure of the scheme to operate. There are no system impacts for inadvertent operation of the scheme.
Study results indicate that the Standpipe LAPS is still necessary to mitigate low voltage conditions on 230 kV system near Badwater and Spence substations following the N-1 loss of the Platte to Standpipe 230 kV line in conjunction with heavy output from wind generation facilities in south-central Wyoming.The scheme is effective, with no system performance violation following the actions of the LAPS.
This RAS assessment included the following:
Study Years
2014
System Conditions
Simultaneous heavy transfer conditionson TOT4A and TOT4B in conjunction with wind generation heavy generation in south-central Wyoming
Contingencies analyzed
(select what applies)
N-1
N-1-1
N-2
Extreme
N-1
Date when the technical studies were completed
2014
Does the RAS comply with NERC standards and WECC Criteria?
Yes
Discuss any coordination problems found between this RAS and other protection and control systems during this (most recent) assessment.
None
Provide a Corrective Action Plan if this RAS was found to be non-compliant or had coordination problems during this (most recent) assessment (should be NA for owner’s initial assessment).
N/A
Additional Notes
N/A